Yv. Egorov et Va. Kondratiev, ESTIMATES OF THE FIRST EIGENVALUE FOR THE DIRICHLET PROBLEM, Comptes rendus de l'Academie des sciences. Serie 1, Mathematique, 322(2), 1996, pp. 129-131
The problem of existence of the extremal values of the first eigenvalu
e for the Dirichlet problem is considered. The essential characteristi
c of the domain is the Minkovsky dimension of its boundary.